First off, I understand why companies do this. There are a couple reasons they do this.
However, I'm an introvert. I understand some of you reading may not be, so perhaps you'll have a hard time relating. Ignore that feeling while reading this and please try to provide an objective response this post if you can. I'm not posting this to start a digression about remote work or people's personalities.
Are there any companies that don't do this? Are there any companies that let you actually work remotely without these week long excursions?
As a fairly introverted person these things fill me with some amount of dread. Luckily haven't had to attend any so far, but I don't know how long that will continue.
The raise of remote work has been a blessing and a curse in this respect -- for me at least.
A) Find a company that is 100% remote (fairly common), does no in-person meetings (rare), is a great place to work (extremely rare), pays the salary you want, and is hiring people like you. It's likely that most of the time, there are zero companies that fit these criteria.
B) Find a company that is 100% remote and does only a few in-person meetings, then work on your aversion to socializing in therapy. Anxiety and fear are very treatable, and life is full of things that you can be very afraid of if you successfully avoid them. You may never become more extroverted, but that doesn't mean you need to be stuck in the prison of being afraid to meet your coworkers once a quarter.
Perhaps, as other people mentioned, having many developers working from overseas, as well as key developers working remotely, disincentivizes the company/department/team from trying to bring them together in-person.